1. Field of the Disclosure
This disclosure generally relates to a thin biometric detection module and, more particularly, to a module that may perform the biometric detection through detecting scattered light from the body tissue after the light passes through the body tissue and without any additional optical mechanism placed upon the semiconductor optical detection pixels.
2. Description of the Related Art
Conventionally, the optical module for detecting biometric characteristics is generally used to detect the finger so as to obtain the biometric characteristic information. According to the user's operating condition, “steady type” and “moving type” can be divided. In the “steady type”, the finger is put steadily on the detection module during detection. In the “moving type”, the finger is sliding over the detection module during detection. In order to obtain good optical imaging, generally optical mechanisms are necessary in order to form the imaging and thus the module has a notable size, e.g. the fingerprint detector provided by NEC with a serial number PU900-10.
With the improvement of life, portable electronic devices, such as notebook computers, cell phones and tablet computers, have become popular. As these kinds of products have the advantage of compact and light weight, the biometric detection module having a large size is not suitable to be applied to these portable electronic devices. Accordingly, the biometric detection module presently applied to the portable electronic devices almost adopts electrical detection technique. Taking the capacitive fingerprint detection module as an example, the module has a detection surface and when a finger is put on the detection surface, peaks and valleys of the fingerprint have a distance difference that can derive different electric field signals. These electric field signals are processed to indicate the finger image that will be compared in the following procedures.